Divide and Conquer, NL West

Home is Where the Wins Are (Not)

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The Colorado Rockies aren't winning at home this year, and that is a problem. One of the franchise's trademarks in recent years has been the ability to dominate opponents at Coors Field (all numbers are through games of Sunday, June 26):

The Rockies have enjoyed much greater success at home than on the road over the past four seasons. Their home/road winning percentage differential has exceeded MLB average in each of those seasons, and usually significantly:

Rockies and MLB, Home vs. Road 2007-2010

Year

Rockies

MLB

Home

Road

Diff*

Home

Road

Diff*

2007

.622

.481

+.140

.542

.458

+.084

2008

.531

.383

+.148

.556

.444

+.113

2009

.630

.506

+.123

.549

.451

+.097

2010

.642

.383

+.259

.559

.441

+.118

2007-2010

.606

.438

+.168

.551

.449

+.103

*May contain rounding errors

Take away home dominance, and you take away much of what makes the Rockies tick. The last time they had such a poor record at Coors Field was in 2005, when they went 40-41. That team also went 27-54 on the road en route to the National League's worst record (they tied with the Pirates, but Pittsburgh had a better run differential; besides, “tied with the Pirates” doesn't impress anyone).

If this year's Rockies were winning at home the way they did over the previous four years (.606 WPct), they would have four more victories to their credit; they would be 42-35, which far from first place San Francisco's current 44-34 record.

The Rockies were expected to contend in 2011. To the extent that a general disinterest in winning the division has taken hold, they still stand a better chance of doing so (we've got them at 6.6 percent to take the division and 14.7 percent to reach the postseason) than one might expect from a sub-.500 ballclub at the end of June.

Getting greater production at home out of several regulars would help. Chris Iannetta (.295/.438/.636), Seth Smith (.323/.373/.586), and Carlos Gonzalez (.327/.394/.558) are doing their part, but how does Troy Tulowitzki hit .272/.323/.476 at Coors Field? This isn't terrible—think Vernon Wells or Torii Hunter career numbers—but for a place that boosts offensive performance to such an extreme degree, “not terrible” isn't good enough.

Tulowitzki's home/road splits this year are baffling. He is losing .024 points of slugging at Coors, which for his career gives him an extra .079. Still, at least he has returned from the little break he took from hitting in May.

It is curious that the friendliest hitting environment in baseball seems to give the team that plays half its games there a bigger boost than most teams receive at home. At the opposite end of the spectrum are the San Diego Padres, whose Petco Park destroys offense and yields minimal home-field advantage.

We've touched on this earlier, but it’s worth revisiting in light of how both Colorado and San Diego are performing at home this year. Granted, the Padres were not expected to duplicate—or even come close to duplicating—their success of a year ago, but if they could win every once in a while at Petco, they might be contending for something other than the first pick in next year's draft (although the Astros seem to be pulling away in that race).

The Padres have closed the gap since the last time I ran numbers (I don't remember the exact date, but my spreadsheet had them at 9-20 at home versus 15-11 on the road, which means they've gone 7-7 and 3-7, respectively, since then). The fact that a -.128 differential represents improvement is alarming.

Again, to place the Padres' performance in context, let's see how it compares with the rest of baseball:

Padres and MLB, Home vs Road 2007-2010

Year

Padres

MLB

Home

Road

Diff*

Home

Road

Diff*

2007

.580

.512

+.068

.542

.458

+.084

2008

.432

.346

+.086

.556

.444

+.113

2009

.519

.407

+.111

.549

.451

+.097

2010

.556

.556

.000

.559

.441

+.118

2007-2010

.522

.455

+.066

.551

.449

+.103

*May contain rounding errors

Consolidating everything into one table, here is how the two teams and other MLB clubs compare over the period 2007-2011. We're just looking at home/road winning percentage differentials this time, and I've also added the current season so you can see how anomalous it is:

Year

Padres

MLB

Rockies

2007

+.068

+.084

+.140

2008

+.086

+.113

+.148

2009

+.111

+.097

+.123

2010

+.000

+.118

+.259

2011

-.128

+.053

+.013

2007-2011

+.044

+.103

+.152

*May contain rounding errors

The question of why an extreme hitters park would favor its home team so much more than an equally extreme pitchers park is a fascinating one that probably deserves to be studied further some offseason. The question of why both teams are struggling at home even relative to their own standards also merits consideration. It has particular urgency for the Rockies, who might be able to fix the problem if they can diagnose it properly before the Giants or Diamondbacks take control of the division for good.